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Interesting Philosophy


ClaudeJ1

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Loudspeakers



Loudspeakers should not be bass reflex. No dipolar operation in any forms.
No synthetic driver’s cones. The wider dynamic range is better but after
110dB/W the Transient/Tone balance rapidly goes down. No impedance equalization,
no resonators of any kind. No crossovers more then 6db/octave if possible; in very specific
cases higher order might be used but very reservingly, very “creatively” and with
the very well-determined purpose. Loudspeakers should have more then 3 channels and
the channel should be painstakingly and meticulously time-aligned not only geometrically
but also acoustically. Any minute phase discrepancy between the channels religiously tabooed.
Loudspeakers should be viewed only in context of their listing
environment and should be positioned according the DPoLS concept (search my site for
further explanations). The “quality” of the loudspeakers should bear ONLY on the quality
of drivers and the loudspeaker design should recognize and to embrace (not combat!) the
idiosyncrasies and the craving of the drivers, and consequentially the design should
furnish the best possible environment for the drivers to let them operate at thier full
blossom. Horn loaded loudspeakers are the most advanced topology of any loudspeaker. The
properly implemented horn-loaded loudspeaker is more superior topology then juts “horn-loaded
loudspeakers”. The properly implemented and advancely performing home-based horn-loaded
loudspeakers are practically unknown to wide audio public.




They were my very basic principles according which I shaped my playback.
If you do not like them…
then I have others....

Romy the Cat from the "Good Sound Club" site.

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I buy all of it except the time alignment and phase stipulations.

I don't buy the time alignment arguments because I don't see it happening in live music - bands, orchestras, choirs, etc. If it is not critical or even possible to time align live performance, why worry about playback?

I don't buy the phase arguments because virtually all recorded music has been phase shifted thousands of degrees between the mic and the tape. A few more degrees can't really hurt, can they?

The time alignment and phase things might be important so someone producing an audiophile recording using very special mic placement and other techniques, no mixing, no editing, maybe no mastering. I did not choose my gear to play just a couple of perfect records... not that there is anything wrong with that!

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Time alignment? This makes my brain hurt, how to you get a 60 foot wavelength and a 2 inch wavelength in the same time (phase). I don't have a good understanding of this and I'm guessing since individual drivers cover a broad range of frequencies that time alignment only can occur at a single frequency. Am I missing the basic concept?

Thanx, Russ

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Pet theories and philosophies are nice. I've got a few myself. They are very comforting until something comes along to blow them out of the water, which happens to me fairly often. Maybe your philosophies are more robust than mine, though!

I'm always, at least subconsciously, trying to conform my audio systems to whatever my current theory of THE ONE RIGHT WAY TO AUDIO NIRVANA is. Trouble is, Audio Nirvana has no permanent address. It's a moving target, depending on your latest point of reference: a live concert experience that blows you away; a listening session with the latest, greatest audio thingy to roll down the pike....whatever. TODAY though, my theory is to enjoy the music in whatever way works for you and your music!

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“How do you get a 60 foot wavelength aligned with a two inch wavelength?”

Easy. They both must “start” at the same place and time. Therein is the caveat. It will most likely require two very different drivers to produce each of those two wavelengths (frequencies 19Hz & 6700Hz). So the question actually becomes “How do you get two drivers required to produce 19Hz and 6700Hz frequencies to occupy the same place and space (in time)?”

You can’t. At least not in the known world we live in.

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don't buy the time alignment arguments because I don't see it happening in live music - bands, orchestras, choirs, etc. If it is not critical or even possible to time align live performance, why worry about playback?

I don't buy the phase arguments because virtually all recorded music has been phase shifted thousands of degrees between the mic and the tape. A few more degrees can't really hurt, can they?

The time alignment and phase things might be important so someone producing an audiophile recording using very special mic placement and other techniques, no mixing, no editing, maybe no mastering. I did not choose my gear to play just a couple of perfect records... not that there is anything wrong with that!

Time alignment does not involve the spacing between performers, but rather the spacing between the drivers in a loudspeaker system. Whenever there are two or more sources reproducing the same sound anomalies will occur. When the multiple sources are separated in time by more than 10 milliseconds or so, two distinct sounds, as in an echo, will be heard. This is not good. If the sources are separated by less of a time interval a comb filter will result. Comb filters cause a rough frequency response curve and lobing. Lobing causes a rough polar response which results in the sound reflecting off of the walls causing time smear and poor imaging.

Irregular frequency response, time smear, and poor imaging. Not what we want. Proper time alignment of the drivers within a loudspeaker system eliminates and/or reduces those problems.

The time/level shift between the performers in a recording is what allows us to perceive the stereo effect. A system with bad time alignment between its drivers interferes with that effect, affecting the realism of the reproduction.

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Heh, heh, heh.......Romy [the Cat] and his posts have been controversial for years.........those comments are just scratching the surface.

Just wait until he finds out about this thread and interjects himself into it.........

Carl.

Very true Carl. That's actually the most coherent thing from him I've ever read.

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These statements usually work better when they are, at least, gramatically correct:

"The properly implemented horn-loaded loudspeaker is more superior topology then juts “horn-loaded loudspeakers”. "

Should read: "The properly implemented horn-loaded loudspeaker is superior topology then juts “horn-loaded loudspeakers”. "

Now isnt that more better......[:^)]

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Well, since I'm the one who pasted the quote, I had a chance to correct the spelling and grammar, but then, it wouldn't be a quote.

The message is more interesting and the grammatical deviations, perhaps, add a touch of personality to the comments, if nothing else.

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don't buy the time alignment arguments because I don't see it happening in live music - bands, orchestras, choirs, etc. If it is not critical or even possible to time align live performance, why worry about playback?

I don't buy the phase arguments because virtually all recorded music has been phase shifted thousands of degrees between the mic and the tape. A few more degrees can't really hurt, can they?

The time alignment and phase things might be important so someone producing an audiophile recording using very special mic placement and other techniques, no mixing, no editing, maybe no mastering. I did not choose my gear to play just a couple of perfect records... not that there is anything wrong with that!

Time alignment does not involve the spacing between performers, but rather the spacing between the drivers in a loudspeaker system. Whenever there are two or more sources reproducing the same sound anomalies will occur. When the multiple sources are separated in time by more than 10 milliseconds or so, two distinct sounds, as in an echo, will be heard. This is not good. If the sources are separated by less of a time interval a comb filter will result. Comb filters cause a rough frequency response curve and lobing. Lobing causes a rough polar response which results in the sound reflecting off of the walls causing time smear and poor imaging.

Irregular frequency response, time smear, and poor imaging. Not what we want. Proper time alignment of the drivers within a loudspeaker system eliminates and/or reduces those problems.

The time/level shift between the performers in a recording is what allows us to perceive the stereo effect. A system with bad time alignment between its drivers interferes with that effect, affecting the realism of the reproduction.

I'm not convinced. Here's my best argument:

If time alignnment anomalies were a real thing, wouldn't one suffer hearing it even on a geometrically perfectly aligned set of drivers every time one leans over to pick up one's drink or pipe, scratch an itch, turn one's head to smile at one's girl, or pet the dog?

Any sound in other than a free space or anechoic chamber (or head phones, and you know how unnatural they sound) will bounce off surfaces and produce a more complex sound comprised of echos of continous degrees of delay with variable shifts in phase and timbre. Seems to me that all natural listening environments will include some levels of reverberation, combing, frequency response variation, lobing, and many other deformations of the sound. I can see how extreme cases of these will goof up the sound to the point where it sounds lousy, but ultimately these things don't completety ever go away, nor would one want them to totally go away. I think these deformations of the sound are desirable to a natural playback to the degree that they stay under the threshold of not intruding into the music.

I don't think time alignment can correct all these deformations anyway, maybe just a small part of them.

I guess another way of thinking about it is that I get excellent realistic reproduction with my La Scalas, which should have some time alignment error because of almost a two foot difference between the tweeter and midhorn drivers, yet the integration sounds spot on perfect. Maybe the type A crossovers reduces the effect, or maybe the amount of the effect is still inside the envelop below which it is not possible to hear.

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If time alignnment anomalies were a real thing, wouldn't one suffer hearing it even on a geometrically perfectly aligned set of drivers every time one leans over to pick up one's drink or pipe, scratch an itch, turn one's head to smile at one's girl, or pet the dog?

The degree of success in time-aligning a loudspeaker system depends on the crossover frequency and the driver spacing. This is because the lobe null angles should be matched to the polar patterns of the two drivers being crossed, both horizontally and vertically, for coherent summation. If one is crossing a tweeter to a midrange at 6kHz, for example, it is nearly impossible to get time alignment because of the short wavelengths involved. less than 2 1/2 in. The center-to-center distance between the midrange and the tweeter would have to be less than that to get the nulls where they do not interfere with the dominant lobe.

This cannot happen unless the mid and tweeter are coaxial, or a unity horn or some other type of summation aperture waveguide are used.

This is the big reason that using electronic delay for time-alignment at high frequencies is less than successful. If you move your head just a bit from the alignment point, then the time alignment is off.

And this is also the biggest reason that loudspeaker designers try to use the fewest crossover points possible consistent with adequate power handling and output, and why they try to get the crossover point as low as possible.

With a lower crossover point the wavelengths are longer, nearly 3 feet at 400 Hz, for example. It is much easier to get the center-to-center distance between the woofer and midrange drivers less than that, so successful time alignment can be achieved and coherent summation can occur.

I don't think time alignment can correct all these deformations anyway, maybe just a small part of them.

Correct, for higher frequencies.

I guess another way of thinking about it is that I get excellent realistic reproduction with my La Scalas, which should have some time alignment error because of almost a two foot difference between the tweeter and midhorn drivers, yet the integration sounds spot on perfect. Maybe the type A crossovers reduces the effect, or maybe the amount of the effect is still inside the envelop below which it is not possible to hear.

The type A crossover sounds the best to many in terms of frequency response but causes more lobing than a steeper slope crossover would. If they sound good to you, I wouldn't lose any sleep over it.

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Any sound in other than a free space or anechoic chamber (or head phones, and you know how unnatural they sound) will bounce off surfaces and produce a more complex sound comprised of echos of continous degrees of delay with variable shifts in phase and timbre.

Right...and the artist is very carefully capturing the correctly delayed sounds. It is part of the timbre of the original recording. If your playback system does not preserve time-alignment, then you are no longer holding true to the intents of the artist.

You claim that it shouldn't have any audible effect, but have you ever sat down with a device that can continuously adjust the delay of a single driver in the system and listened to the sound change as you change the delay?

Or to put it another way, why can I time-align a system by ear? Even when the recording has a bajillion different sources of time smear? I find that it's easiest to hear when listening to a good recording with a fat snappy snare.

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With a lower crossover point the wavelengths are longer, nearly 3 feet at 400 Hz, for example. It is much easier to get the center-to-center distance between the woofer and midrange drivers less than that, so successful time alignment can be achieved and coherent summation can occur.

Well, right now I'm using a great super tweet which, I know is not time aligned, but I don't care. PWK told me that was the least detactable anomaly.

According to Tom Danley, whose Synergy horns are so time aligned (they will pass square waves for a decade of frequencies) you need to stay withing 1/4 wave to achieve this, which means at my 900 Hz. Xover point from Mid Bass to Mid Horn, I'm looking at about 3 1/2 inches, which isn't completely happening there either. But, I say, the closer the better, where it counts.

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Time and phase alignment makes complete sense on paper. But a klipschorn sounds about a million times better than a Thiel, so who cares?

God I love it when you talk sense.

Dave

PS-Wonder what a violin designed by scientists would sound like?

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